[ninglinLiu]

Link to Issue or Description of Change

2. No issue (small documentation fix):

Problem:
src/google/adk/cli/built_in_agents/README.md still describes an older layout/API of the Agent Builder Assistant:

• adk web src/google/adk/agent_builder_assistant and from google.adk.agent_builder_assistant.utils import ... point to a package that no longer exists (it lives under google.adk.cli.built_in_agents).
• The programmatic examples and the "Schema Modes" section pass schema_mode=... to AgentBuilderAssistant.create_agent(), but the method only accepts model and working_directory, so the examples raise TypeError.
• The "Tool Ecosystem" list includes google_search, url_context and resolve_root_directory, which are not registered on the assistant, and omits cleanup_unused_files, which is.

Solution:

• Update the adk web path and the utils import to google.adk.cli.built_in_agents, and add the AgentBuilderAssistant import to the programmatic example.
• Drop schema_mode and replace the two-mode section with a short note that the AgentConfig schema is embedded in the instruction.
• Make the tool list match the FunctionTools registered in adk_agent_builder_assistant.py.

Testing Plan

Docs-only change. Checked the module paths and names against src/google/adk/cli/built_in_agents/ (__init__.py, utils/__init__.py, create_agent() signature, and the custom_tools list).

Checklist

• I have read the CONTRIBUTING.md document.
• I have performed a self-review of my own code.

AI-assisted: drafted with an AI coding assistant and reviewed before submitting.

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